Metal coated glass fiber combinations



:aswamsg SR INVENTOR. JOHN A; Gen/v7" OR IN? ST/1406* Dec. 8, 1959 lJ.IA.I GRANT 2,915,506 I v mp1. comm GLASSFIB'EZR cowanmnoxs I W Filedrm. 9'. 195a ATTORNEYS I 2,915,806 V v METAL COATED GLASS FIBERconrnnvanozss John A.Grant, New ark, Ohio, assignor to Owens-CorningFiberglas Corporation, a corporation of Delaware Application November 9,1953, Serial N o 391,054

9 Claims. c1. 23-41 'lhis invention relates to glass fibers andparticularlyto glass fibers coated with materials to'provide strands,

yarns and other textiles .havirg increased wear or abrasion resistanceand increased fiexural life.

Patented Dec. 8, 1959 to the product.

It is another object of this invention to provide a coating for glassfibers for protection 'of theirsurfaces and to permit formation ofgroupings of the glasstibers hav ing dissimilar coating materials andthereby to promote .retention of their tenslle strength and anincreasein their flex life in products and other instances where thefiben' are caused to slide against eachother when in pressure contact-I\ a It is another'object of invention to'provide ,an -K economical highspeed method of making strands of glass 7 fibers hayingcoatings ofmorethan one type.

It is well-known that glass fibe s have extremely high tensile strengthsbut that at times they are somewhat limited inapplication by thefactthat in general, they have low resistance to forces of abrasion.Bare glass fibers when rubbed against each othcr'produce surfacescratches which result in considerable reduction in thetensile'strength. In other words, the usable strength is often too lowfor specific applications. As an example, strands made of a plurality ofbare glass fibers have tensile strengths practically equal to a multipleof the tensile strength of an individual fiber, but when such a strandis worked, as by flexing, or by twisting and-plying, abrasion occurs atthe interfaces of the fibers to inflict surface damage such that thetensile strength of the combination of fibers is greatly reduced. With aproduct such as this, the flexural life, or the number of times thestrand may be flexed is quite limited.

It has been found that glass fibers may be coated withmaterials such asmetals to protect the surface and thereby retain the tensile strength ofthe fibers and at the same time greatly increase the flex life ofgroupings of 'fibers incorporated in a product. A long fiex life isparticularly desired in instances when glass fibers are to be utilizedin yarns, cords, and ropes, or in fabrics such as sail cloth, awningmaterial or tire cords where the material is subjected to considerablemovement resulting in substantial wear at the interfaces of the fibers.

The wear properties at the interface of two surfaces of the samematerial, however, are not always ideal or even desirable. For instance,it is well known in the field of bearing manufacture that a steel faceacting against an:

' other steel surface does not product a good'bearing interface.Correspondingly, a bronze surface against another surface of the samebronze does not provide a particularly good bearing interface. A bronzesurface against a steel surface, however, results in an excellentbearing interface combination. This combination results in betterhearing characteristics than when only one of the two 1 metals is*usefdin each of the contacting surfaces forming an interface; One advantageof the use of dissimilarmetals is that frequently galling and seizurecan be mini mized. Use of one material in a combination with a highelastic limit is also a method by which plastic deformation may bereduced to prevent seizure under pressure. The use of one metal in acombination having a lubricatirrg film or" oxide coating, or a sulfide,chloride or phosphate coating has also been found to be helpful inimproving the lifeo'f surfaces acting against each other.

In view of the foregoing, it is an object of this invention toprovide astrand of glass fibers coated with dis- Similar and complementarysurface materials such that upon being grouped in such products asstrands, yarns,

It is still another object of this invention to provide a higherabrasion resistance in glass fibers grouped into products by coating thefibers with-dissimilar materials having complementary physicalproperties in resisting damage from abrasion when movement is effectedat their interfaces. I a g A further object of this invention is toprovide a fabric -madeof glass fibers coated with-dissimilar materials tso arranged as to impart to the fabric the advanu. increased abrasionresistance of. the coating materials.

It is a feature of this invention that the applicationbf coatingmaterials to the glass fibers may be effected-in the fiber-formingoperations, thereby eliminating the need for treatment on a specialhandling basis and promoting economical production of coated fibers.

It is another feature of this invention that coating mate rials may beapplied to the fibers at any of a range of temperatures in thefiber-forming operations, thus making the coating procedure flexiblyadaptable to selectively fibers or filaments for incorporation in astrand made in accordance with the present invention;

Figure 2 is a partially broken away front clevational view of theapparatus shown in Figure l;

Figure 3 is a perspective view of the end of a strand made up of fiberscoated with dissimilar materials;

Figure 3a is a perspective view of the end of a strand of orientedfibers coated with three dissimilar materials;

Figure 4 is a perspective view of the end of a cord made up of glassfilaments coated with dissimilar materials; and Figure 5 is a view of apiece of woven fabric made of strands of glass fibers coated withdissimilar materials.

The principles of thepresent invention have been chosento be explainedherein with regard to' a method by which metal may be coated on glassfibers'during forming.

Turning tothe drawings in detail, Figures i and 2 showra general layoutof fiber-forming and metal-coating apparatus including a suitablereceptacie and feeder 10 for 1 molten glass that may be heated in anyconventional man ner. The feeder 10 is provided with a series ofoutlets12 in its bottom front which fiow a plurality of streamsof molten glass.Preferably,- the outlets are all arranged in one or two rows so that thestreams as they ilow from the outlets can be readily divided into twoseparate groups of fibers 13 and 14 for application of separate metalsthereto.

If desired, however, more than two rows of outlets may be provided toflow streams that may be divided into groups.. As the streams flow fromthe outlets 12 they are drawn out into fibers or filaments 13 and 14 bymeans of a J rotating drum or a collet supported tube 16 which winds thestrand while pulling on the filaments to draw out the streams.

A pair of separator rollers 17 and 18 which form a more positivedivisionbetween the filaments 13 and 14 and a spinner-type gatheringmember 19 for collection of the filaments into a group or strand 20 areprovided in positions intermediate the source of the streams of moltenglass and the forming tube 16. Sizing materials may beapplied to thefilaments at the separator rolls' 17 and 18.

Sizing materials such as that "set out in United States- Patent 2,234,896,'issued,on March 18, 194cm: sizing matcrialsl'which are predominantlylubricant .in nature, such as petroleum oil, vegetable oilmolybdenurn'disulfide,

for other recognized lubricantsfor metal may be used.

After thestrand is formed, other treatment such as finishes might'beapplied to adapt it to specific uses. For

example, when combining metal-coated fibers with rubber, a finishisoften used having one component common to both the adhesive and thefinish. More specifically, if the constituents, then the finish likewisemay have RFL as an ingredient.

The apparatus for applying metal to the fibers as they areforrnedcomprises a pair of similarly constructed-ap' plicators 21 and31. Each applicator has a graphite face properties desired of thematerials.

4 I- peratures if the proper relationships are not established Thus, thelevel atwhich the applicators 21 and 31 ap'pl} the respective materialscontained therein maybe dififlfi depending upon the meltingcharacteristics and phy m correspondingly, the application "of sizingmaterials i rolle: separators 17 and 18 may be done at different levelbelow the point of application of metals to the filament: It should benoted,however, that if the 'metals to 1 applied to the two'groups offilaments are adapted t application at the same temperature levels,"they may b supplied from a common unit with two coating faces lc c'atedbetweenthe groups, thereby making itunnecessar to dispose the rollerseparators between the two group! That is, a commonvmetal applicatorunit could be. mad to functionas a separator unit as well as an'applicawunit, thereby permitting application of sizing materit from the exteriorof the'two fans of filaments, if desiret In tests of the factorsinvolved in the selection of prop: coating metals for combination withina strand, it ha been'discovered that they simulate closely those involvein the selection of metal combinations in the hearing at Tests of flexlife of glass strands with different metal "25 adhesive has resorcinolformaldehyde latex as one of its over which the attenuated filamentspass as theyare being coated. The metal in each of the applicators ismaintained in a molten CoXtIllllOn by heating units such as electricalresist mt' elements conductors of which are embedded within a suitableelectrical insulation layer such as refractory cement or silicatefibers. The heater units are each provided with external terminals forconnection to a suitable power source. c

which provides sufficient retaining force to prevent free flow of themolten metal from the unit and which also suspends the strip in thespace in front of the face without external support. Vertical groovesare provided in the face of the applicators to accommodate the filamentspassed over the respective faces to permit them to" pass through themolten strip or globule of metal closer to its base to assure positiveenvelopment of the filaments. Coating of metal on fibers in this mannerpermits unobstructed filament passage over the faces of the applicatorsv throughthe grooves and additionally eliminates the need formodification of the fiber-forming methods generally muse.

The average temperature of molten glass in the manufacture of mostglasses used in textile fibers is in the order of 2200 F. At a pointsome distance below the feeder outlets 12, this temperature drops'tothat of the surrounding atmosphere. By reason of extension of the dropin temperature of the filaments over an appreciable distance, a range oftemperature levcls'exist from which a selection may be made forapplication of specific metals under most advantageous conditions. Ithas been found that the relationship of the temperature of the metal tothe temperature of the glass at the point of application of themetal isquite important since the strength of the glass fibers may be impairedby extremely high metal temreveal that flex life is considerably higherwhen the ct efiicient of friction is low at theinterface of the materialon the individual fibers. Other properties of metal whic operate withlow friction to improve the wear lifec ab'rading or rubbing surfaces arethe anti-welding charar teristics and compressive strength. in .glassfiber prot ucts such as rope or fabric materials for sail cloth, aw:lugs, or tire cords where considerable flex working is. er countered,the ability of the coating material to comfort to contours at itsinterface, in other words, its modult of elasticity, is an importantfactor. A further and higl 1y important factor'is the metallurgicalstructure of ti: materials, particularly at the interface. For each met:coating material, there is a particular molecular or cry: tallinearrangement which is better in performance undt a given set of fiberworking :onditions.

In view of the fact that wear life isa function of t1. coaction of allthese factors, each of which is a compl cated phenomenon when consideredalone-in detail, will be apparent that a universal optimum materialcombination of materials will not readily be found. B proper selectionof dissimilar complementary material however, the wear life of groupingsof glass fibers, suc as in strands, fabrics and cord products, can beincrease appreciably over the life of corresponding products mac offibers coated with either material of such combinatior alone. Theselection of combinations, providing in proved wear life, however,usualiy entails a trial and em mating for each specific applicationbased on previot 'wear experiences'and knowledge available from theheat; ing art.

Figure 3 shows a strand 20 of glass-fibers each of-whic. is individuallycoated with a material, but some of ti fibers being coated withonemate'rial 31 such as zinc whi the remainder are coated with anothermaterial 32 (desig natedby a line through theiglass core) selected for icomplementary, physical characteristics in providing'lor wear'life tothe-strand. Similar coatings on filamen of each of the strands shown inFigures 3 and 3a are di tinguished by dot and dash identification marksas we 'asthe absence of marks on the ends of the glass 51;

merits. It will be noted here that. the fibrs'are group: together insomewhat random arrangement within tl strand which on consideration willindicate that a inax mum number of interfaces of dissimilar materials winot always be provided. The increas :1 life of' such rad domly groupedfibers, however, is submitted to be a resu of the fact that at leastsome of the interfaces heir formed by contact of dissimilariy coatedfibers resul when fibers coated with one material are located on or sideof a line passi g ugh the strand while all fibe; coated with anothermaterial lie on the opposite aid bined in product groupings of coated.fibers as wear re- "sistant combinations include zinc, copper, aluminum,

nickel, tin, lead, alloys of these metals and others. For

-'example, zinc which hasa melting point of 786?.1. and a hardness ofapproximately 100 'Brinell can be coated on glass fibers andadvantageously associated for wear with fibets coated with' a tin basealloy such as Babbitt." metal having a composition of 65.5% tin, 18.2%lead,

14.1% antimony and 2% copper having amelting point of 358 F. and ahardness of about 23 Brinell. Additional metal combinations which may becited as examples in-'' -ciude heavy-duty lead base Babbitt withzincbasebearing alloys, stainless steel with leaded tinbronze,-'aluminurn -oase alloys and bronze, steel and graphite bronzeand numerous others. In view of the range of physical propertiesobtainable in the difierent'type's of alloys falling within broadclassifications such as zinc base alloys, combinations of alloyscomplementary in physical properties but of somewhat similarcompositions will often provide dcsirable increase in wear resistance.

The oxides or other compounds of the metals when formed on the coa ingsurface often give an increased wearability. The incorporation or onemetal that forms a sort of lubricating film or a thin coat of sulfide,chloride or phosphate often has this cfiect and the selection ofcombinations are made with these facts in mind. It is also possibile .inmany instances to plate one metal with indium to increase wearresistance. Indium has an additional advantage in that'it protectsagainst corrosion.

It should be noted that improved wear life according to the presentinvention is not necessarily limited to mating of metals only, but theprinciples are intended to be extended to metals cornplcmcntarily matedwith other materials such as graphite coated on glass as by drawing thefibers through wax and then applying graphite particles, as well as tomating of othcr dissimilar nonmetallic materials adapted to providinglong contact life as bearing-like combinations.

Figure 3a shows a strand with or. oriented arrangement of fibers coatedwith three different materials illustrating how all interfaces of thefibers can be formed by contact of different materials to prolong wearlife. Three types of interfaces exist in the arrangement; one formed bycontact of fibers coated with materials 36 and 37,

. another by fibers coated with materials 37 and 38, while the third isformed by fibers coated with materials 38 and 36. Itshould be noted inthis arrangement that one of the groups of fibers might be left barewithout deviating from the principles of the invention. I

Figure 4 shows a glass fiber cord made of twisted strands of the typeshown in Figure 3. It will be -recognized that the number of interfacialcdntact points between the dissimilar material will tend tobe greatlymultiplied by twisting of the individual strands, and'that the furthertwist of the strands .over each other will promote even more approach toa maximum number of such contact points between dissimilar materials.

with the principles of this invention including yarns in- The greaterthe distribution in. random arrangements other than this definitedivision, the larger is the number I i Figure 5 shows a woven fabric- 50made in accordance.

rials. It is to be understood that the fabric maybe woven of yarns madeof strands similar to that shown in Figure 3 and that the maximum numberof interfacial contacts by dissimilar materials will be promoted by theapproach to thorough distribution as in the cord of Figure 4, but asillustrated in the present instance, the fabric has been shown as wovenwith yarns each of which has all of its filaments coated with the samematerial. Thus,

the yarns 51 woven in one direction have fibers coatedwith "one materialwhile the yarns 52 extending crosswise at a angle thereto comprisefibetscoated. with another material complementary to the first toprovide'improved wearability. The crossover points of yarns on thisfabric,

it will be noted, areall formed by anoverlay or contact of yarns of thedissimilar materials, and tendencies toward.

contact by portions of yarn. surfaces of similar coating materials arealmost negligible'in view of the form of the weave. Thus, the increasedwear afforded-by contact of dissimilar materi alsis positivelyincorporated in the v fabric. 4

In view of the various illustrated forms in which fibers of d ssimilarmaterials can be incorporated for increased.

wear of 'glass fibers in textile. products, it is apparent that thebasic principles of this invention havebroad application in improvingthe wearability of the coated glass fibers.

While "I have shown certain particular forms of the}v invention, it willbe understood that I do not wish to be limited thereto since manymodifications may be made within the concepts ofthe invention, and Itherefore contemplate by 'the appended claims to cover all suchmodifications. that fallwithinthe spirit and scope of the invention. I

I claim:

1. A strand. of glass fibers comprising fibers each indi vidually coatedwith metal, a group of said fibers each having an exterior surface ofone metal and a second group each having an exterior surface of anothermetal.

the metals on said fibers being compatible for wearability in slidingcontact with each other. 2. A strand ofglass fibers comprising o e groupof fibers individually coated with a metal and a layer ofoxide of thesame metal thereover, and another group of fibers individually coatedwith a second metal-and a layer of oxide of the second metal thereover,said oxides being compatible for wearability in sliding contact witheach other.

3. A strand of glass fibers comprising one group of fibers individuallycoated with a metal and a compound of the same metal thereover andanother group of fibers individually coated with a second metal and acompound of the second metal thereover, said compounds being compatiblein sliding contact with each other.

4. A'cord made of coated glass fibers comprising intettwisted strands offibers each of which comprises a group of fibers individually coatedwith one metal and another group individually coated with a second metaladapted to function with said one metal in providing a high wearresistance in sliding contact with said first metal.

5. A yarn made of coated glass fibers comprising I twisted and pliedstrands of said fibers, each of said strands comprising fibers coatedwith dissimilar compati- Y ble metals complementary in physicalproperties to impart improved wearability in .sliding contact betweenfibers. Y

6. A yarn of glass fibers comprising three groups of fibers, each groupcomprising fibers having-an external surface material similar 0t that onthe other fibers inthe group, the external surface material of the threegroups being dissimilar metals and any two such metals beingcomplementary in physical wear properties in sliding contact with eachother. I I 7. A strand of fibers comprising a group of glass fibersindividually coated with a first metal and another group glass fibersindividually coated with a second metal com-' patible in sliding contactwith said one metal and a third group of fibers having an exteriorsurface compati- N ,....s......v,.....,.... -s...

b1: with the metal coatings of said other two rou s of 2,272,588 SimisonFe 1 194?- fiber s J 2,373,078 Kleist Apr- 1945 9. A fabric made ofyarns of metal coated glass fibers, 2,454,830 Ne'wt'on NO 3 1948 m: yamsof said fabric compzising twisted strands of 2,485,019 Somerville 041 11949 said fibers, said fibexs being coated with dissimilar com- 52,509,894 Tculmin, et a1. May 30,1950 patiblc metals complementary inphysical properties to ..'2,663,989 Schlatter Dec. 29. 1953 impartimproved wcarability in slidiizg contact betwcen 2,699,415 Nachtman Jan-1955 fibers. I 1 2,720,076 Sachara Oct. 11, 1955 2,767,519 7 BjorkstenOct. 23, 1956 References Cited in the file of this patent 19 2,772,518 wi et a. Decj, 41956.

UNITED STATES PATENTS 2,090,541 -Ncavcs Aug. 17, 1931 Y FOREIGN P S i1,224,274 Powers Dec.10,1940 1,5 9; f3tB1itiin.; 0: 1853

7. A STRAND OF FIBERS COMPRISING A GROUP OF GLASS FIBERS INDIVIDUALLYCOATED WITH A FIRST METAL AND ANOTHER GROUP OF GLASS FIBERS INDIVIDUALLYCOATED WITH A SECOND METAL COMPATIBLE IN SLIDING CONTACT WITH SAID FIRSTMETAL